Variable scope within an interface and some questions

Question

I am creating a DataStorage interface with a member variable (can I call it a member variable when it is in an interface?) called dataObject. From what I remember, and what the compiler is telling me, the scope declarations "private," or "protected" can not be used on either methods or member variables in an interface.
Now I have another class DataInput that implements DataStorage and I want to make the dataObject private and put in accessor methods to get to the dataObject. But I also remember reading something that said, during inheritance you can not make the scope of the method (and variable?) more narrow. Meaning if a method was defined as default in the parent class, the subclass can not override that method to give it private access all of a sudden.
Now a couple of questions with this...does that rule only apply to subclassing (that is with extends) or does it also apply to implementing interfaces. Second question, I am pretty sure that rule applies to methods that are being overriden, but does it also apply to variables in an interface...because if that is the case, I can't re-declare the variable in the class that implements the interface to be private...and then there is no way to protect that variable.
By the way I did re-declare the variable in the subclass (implementing class) and declared it as a private, and it works...but I'm still trying to figure out the general rule.

Answer 1

well if the interface variables are implicitly public static final, how come I am able to re-declare the variable name within the class that implemented the interface.
If for example in interface Car there is a variable color, how come in class Honda implements Car, I can redeclare the variable color, and give it public access. I thought final meant final, no redeclaring...but does that not hold for static variables?